Phytochemical composition, antifungal activity, in vitro and in vivo toxicity of Syzygium cumini (L) Skeels leaves extract / Composición fitoquímica, actividad antifúngica, toxicidad in vitro e in vivo del extracto de hojas de Syzygium cumini (L) Skeels

This study determined phytochemical composition, antifungal activity and toxicity in vitro and in vivo of Syzygium cumini leaves extract (Sc). Thus, was characterized by gas chromatography coupled to mass spectrometry and submitted to determination of Minimum Inhibitory (MIC) and Fungicidal concentrations (MFC) on reference and clinical strains of Candida spp. and by growth kinetics assays. Toxicity was verified using in vitro assays of hemolysis, osmotic fragility, oxidant and antioxidant activity in human erythrocytes and by in vivo acute systemic toxicity in Galleria mellonella larvae. Fourteen different compounds were identified in Sc, which showed antifungal activity (MIC between 31.25-125µg/mL) with fungistatic effect on Candida. At antifungal concentrations, it demonstrated low cytotoxicity, antioxidant activity and neglible in vivotoxicity. Thus, Sc demonstrated a promising antifungal potential, with low toxicity, indicating that this extract can be a safe and effective alternative antifungal agent.

Este estudio determinó la composición fitoquímica, la actividad antifúngica y la toxicidad in vitro e in vivo del extracto de hojas de Syzygium cumini (Sc). Así, se caracterizó mediante cromatografía de gases acoplada a espectrometría de masas y se sometió a determinación de Concentraciones Mínimas Inhibitorias (CMI) y Fungicidas (MFC) sobre cepas de referencia y clínicas de Candida spp. y mediante ensayos de cinética de crecimiento. La toxicidad se verificó mediante ensayos in vitro de hemólisis, fragilidad osmótica, actividad oxidante y antioxidante en eritrocitos humanos y por toxicidad sistémica aguda in vivo en larvas de Galleria mellonella. Se identificaron catorce compuestos diferentes en Sc, que mostraron actividad antifúngica (CMI entre 31.25-125 µg/mL) con efecto fungistático sobre Candida. En concentraciones antifúngicas, demostró baja citotoxicidad, actividad antioxidante y toxicidad in vivo insignificante. Por lo tanto, Sc demostró un potencial antifúngico prometedor, con baja toxicidad, lo que indica que este extracto puede ser un agente antifúngico alternativo seguro y eficaz.

Phytochemistry, antifungal and antioxidant activity, and cytotoxicity of byrsonima gardneriana (A. Juss) extract.

OBJECTIVE: To determine the phytochemical composition of Byrsonima gardneriana (A. Juss) leaf extract (BGE) and its antifungal activity against Candida spp., antioxidant potential and in vitro cytotoxicity. MATERIAL AND METHODS: BGE was obtained and submitted to Gas Chromatography Coupled to Mass Spectrometry for phytochemical analysis. The ethanolic extract was tested for its antifungal activity against C. albicans and non-albicans reference strains and clinical isolates in addition to inhibition of C. albicans growth kinetics. It was also tested for antioxidant potential in the presence of phenylhydrazine and reactive oxygen species (ROS). And cytoxicity in human erythrocytes. The data were analyzed by one-way Analysis of Variance (ANOVA) followed by Tukey's or Dunnett's post-hoc test, with α = 0.05. RESULTS: Pyroglutamic acid (90.77 %), eucalyptol (89.61 %) and octanoic acid (76.22 %) were the major compounds detected in BGE, P (%) is the percent probability of compound identification, according to the mass spectra library. The extract showed fungistatic activity, with MIC of 125 µg/mL against most tested strains. While BGE showed low hemolytic activity on all blood types tested herein, it could not prevent osmotic stress in human erythrocytes. The extract did not have oxidizing effects in the presence of phenylhydrazine, but it showed antioxidant potential against ROS when tested at 31 µg/mL and 62 µg/mL. CONCLUSION: B. gardneriana extract showed antifungal activity against Candida spp., demonstrated low hemolytic potential, no oxidant activity in human erythrocytes and antioxidant activity against ROS. This study opens avenues for the study of BGE as a promising biocompatible antifungal agent.

Use of erythrocytes in cytotoxicity and toxicity assays of medicinal plant extracts: analysis of their application and bibliometric study / Utilización de eritrocitos en ensayos de citotoxicidad y toxidez de extractos de plantas medicinales: análisis de su aplicación y estudio bibliométrico

Plant species have been used for therapeutic purposes since ancient times and are still in use today since these products represent a source of raw material for the production of phytotherapeutic formulations. Screening and investigation of plants with pharmacological potential require the evaluation of characteristics related to their action, efficacy and safety in different steps. Among these steps, pre- clinical trials are used to evaluate the properties of the test product in in vitro experiments, such as cytotoxicity assays. Within this context, this study consists of a bibliometric analysis of some in vitro cytotoxicity and toxicity assays in erythrocytes used during bioprospecting of medicinal plants. The results demonstrated the wide application of erythrocytes to evaluate the biological effects of medicinal plant extracts. The methods were found to be valid and effective for the preliminary investigation of the in vitro cytotoxicity and toxicity of plant products.

El uso de especies vegetales para fines terapéuticos es una práctica histórica y todavía bastante actual, ya que estos productos pueden representar una fuente de materia prima para la producción de formulaciones fitoterápicas. En investigación de plantas con potencial farmacológico requiere la evaluación de su acción, eficacia y seguridad, a través de diferentes etapas. Entre estas, en los ensayos preclínicos se evalúan las propiedades del producto-prueba en experimentos in vitro, tales como ensayos de citotoxicidad, entre otros. En este aspecto, el presente estudio consiste en un análisis bibliométrico acerca de algunas pruebas de citotoxicidad y toxicidad in vitro en eritrocitos realizados en los ensayos de bioprospección de plantas medicinales. Los resultados evidencian la amplia utilización de eritrocitos para la evaluación de los efectos biológicos de extractos de plantas medicinales, apuntándolos como métodos válidos y eficaces para la investigación preliminar de la citotoxicidad y toxicidad in vitro de productos vegetales.

Antibacterial activity against cariogenic bacteria and cytotoxic and genotoxic potential of Anacardium occidentale L. and Anadenanthera macrocarpa (Benth.) Brenan extracts.

OBJECTIVES: The present study aimed to assess the antibacterial activity against bacteria with cariogenic relevance, toxic and genotoxic potential of the plants Anacardium occidentale L. and Anadenanthera macrocarpa (Benth.) Bernam. DESIGN: Using a microdilution technique, the extracts were submitted to minimum inhibitory concentration (MIC) testing against Streptococcus mitis (ATCC 903), Streptococcus mutans (ATCC 25175), Streptococcus oralis (ATCC 10557), Streptococcus salivarius (ATCC 7073), Streptococcus sanguinis (ATCC 15300) and Streptococcus sobrinus (ATCC 27609). The toxicity of the extracts was then verified against eukaryotic cells. Additionally, a micronucleus assay was performed to investigate the potential mutagenic effects of the extracts on rat erythrocytes. The Student's t-test, Bonferroni test, and one-way ANOVA followed by Tukey's tests were used for statistical analysis, at a significance level of 5%. RESULTS: While the A. occidentale extract was able to inhibit all of the tested strains, with S. mutans and S. mitis being the most susceptible to that extract́s action, the A. macrocarpa did not show antimicrobial activity. Interestingly, the hemolytic, oxidant and antioxidant activities were slightly observed for either extract, even at high concentrations (1000mg/mL). The micronucleus assay showed no significant changes in the cells exposed to the extracts. CONCLUSION: The A. occidentale extract has potential as an antimicrobial agent with low eukaryotic cell toxicity or mutagenic activity. The A. macrocarpa extract, although absent of antibacterial activity might as well be a safe and effective phytotherapeutic alternative.

Assessment of Nutrient Value and Microbiological Safety of Pomacea lineata.

Pomacea lineata is a fresh water shellfish that is utilized as food, medicinal portions, or licking remedies. The objective of this study was to evaluate the nutritional and microbiological aspects of P. lineata and spawning. The samples were collected in the Jaguaribe River (Paraíba, Brazil) during the rainy and dry seasons. The biochemical composition, mineral composition, total mesophilic bacteria (TMB), total coliforms (TC), fecal coliforms (FC), Salmonella sp., Staphylococcus aureus, and Vibrio presence were determined. Each 100 g of P. lineata presented 3.1 g of ashes; 9.4 g of proteins; 2.7 g of lipids; 0.6 g of carbohydrates; 1800.0 mg of calcium; 78.0 mg of phosphorus, and 58.4 mg of iron. Each 100 g of spawning presented 10.4 g of ashes; 4.5 g of proteins; 2.8 g of lipids; 1.3 g of carbohydrates; 3633.0 mg of calcium; 39.4 mg of phosphorus; and 4.6 mg of iron. Each 100 g of P. lineata provided 65.7 kcal and spawning 48.3 kcal. In the dry season P. lineata and spawning showed no TMB and TC, FC, S. aureus, Salmonella, or Vibrio. In the rainy season P. lineata and spawning presented increase in TMB and TC, FC, S. aureus, and Salmonella. The presence of Vibrio was not detected. P. lineata presented proteins, low lipid, and carbohydrate content, energy values close to those of lean meats, high contents of calcium and iron, and presented low contamination level with pathogenic bacteria. Since P. lineata substances may be useful in the treatment of respiratory and gastrointestinal diseases without presenting toxic or cytotoxic effects already described in the literature, it may be considered as a potential functional food.

Antinociceptive and anti-inflammatory effects of a lectin-like substance from Clitoria fairchildiana R. Howard seeds.

Lectins are proteins that have the ability to bind specifically and reversibly to carbohydrates and glycoconjugates, without altering the structure of the glycosyl ligand. They are found in organisms such as viruses, plants and humans, and they have been shown to possess important biological activities. The objective of this study was to purify and characterize lectins in the seeds of Clitoria fairchildiana, as well as to verify their biological activities. The results indicated the presence of a lectin (CFAL) in the glutelin acid protein fraction, which agglutinated native rabbit erythrocytes. CFAL was purified by column chromatography ion-exchange, DEAE-Sephacel, which was obtained from a peak of protein retained in the matrix by applying 0.5 M NaCl using the step-wise method. Electrophoretic analysis of this lectin in SDS-PAGE indicated a two band pattern protein molecular mass of approximately 100 and 116 kDa. CFAL proved to be unspecific to all carbohydrates/glycoconjugates in common use for the sugar inhibition test. This lectin showed no significant cytotoxicity to human red blood cells. It was observed that CFAL has anti-inflammatory activity in the paw edema induced by carrageenan model, in which a 64% diminution in edema was observed. Antinociceptive effects were observed for CFAL in the abdominal writhing test (induced by acetic acid), in which increasing doses of the lectin caused reduction in the number of contortions by up to 72%. It was concluded that the purified and characterized lectin from the seeds of Clitoria fairchildiana has anti-inflammatory and antinociceptive activity, and is not cytotoxic to human erythrocytes.